# How do you rationalize the denominator 5/(sqrt(28x))?

You could rationalize the denominator of $\frac{5}{\sqrt{28 x}}$
by multiplying by $\frac{\sqrt{28 x}}{\sqrt{28 x}}$
$\frac{5}{\sqrt{28 x}} \cdot \frac{\sqrt{28 x}}{\sqrt{28 x}}$
$\textcolor{w h i t e}{\text{XXXXX}}$$= \frac{5 \sqrt{28 x}}{28 x}$
Note this could be simplified a little by noting that $28 = {2}^{2} \cdot 7$, so
$\textcolor{w h i t e}{\text{XXXXX}}$$= \frac{5 \sqrt{7 x}}{14 x}$